/****************************************************************************
Copyright (c) 2010-2012 cocos2d-x.org
Copyright (c) 2013-2016 Chukong Technologies Inc.
Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.
Copyright (c) 2019-present Axmol Engine contributors (see AUTHORS.md)

https://axmol.dev/

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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****************************************************************************/

#ifndef __SUPPORT_ZIPUTILS_H__
#define __SUPPORT_ZIPUTILS_H__
/// @cond DO_NOT_SHOW

#include "platform/PlatformMacros.h"
#include "platform/FileUtils.h"
#include <string>

#if (AX_TARGET_PLATFORM == AX_PLATFORM_ANDROID)
#    include "platform/android/FileUtils-android.h"
#elif (AX_TARGET_PLATFORM == AX_PLATFORM_WIN32)
// for import ssize_t on win32 platform
#    include "platform/StdC.h"
#endif

#include "yasio/byte_buffer.hpp"

#include <span>

#ifndef _unz64_H
struct unz_file_info_s;
#endif

/**
 * @addtogroup base
 * @{
 */
namespace ax
{

/** XXX: pragma pack ???
 * @struct CCZHeader
 */
struct CCZHeader
{
    unsigned char sig[4];            /** Signature. Should be 'CCZ!' 4 bytes. */
    unsigned short compression_type; /** Should be 0. */
    unsigned short version;          /** Should be 2 (although version type==1 is also supported). */
    unsigned int reserved;           /** Reserved for users. */
    unsigned int len;                /** Size of the uncompressed file. */
};

enum
{
    CCZ_COMPRESSION_ZLIB,  /** zlib format. */
    CCZ_COMPRESSION_BZIP2, /** bzip2 format (not supported yet). */
    CCZ_COMPRESSION_GZIP,  /** gzip format (not supported yet). */
    CCZ_COMPRESSION_NONE,  /** plain (not supported yet). */
};

class AX_DLL ZipUtils
{
public:
    template<typename _Ty, size_t _Extent = std::dynamic_extent>
    inline static yasio::byte_buffer compressGZ(std::span<_Ty, _Extent> in, int level = -1)
    {
        return compressGZ(in.data(), in.size_bytes(), level);
    }
    template <typename _Ty, size_t _Extent = std::dynamic_extent>
    inline static yasio::byte_buffer decompressGZ(std::span<_Ty, _Extent> in, int expected_size = -1)
    {
        return decompressGZ(in.data(), in.size_bytes(), expected_size);
    }

    static yasio::byte_buffer compressGZ(const void* in, size_t inlen, int level = -1);
    static yasio::byte_buffer decompressGZ(const void* in, size_t inlen, int expected_size = -1);

    /**
     * Inflates either zlib or gzip deflated memory. The inflated memory is expected to be freed by the caller.
     *
     * It will allocate 256k for the destination buffer. If it is not enough it will multiply the previous buffer size
     * per 2, until there is enough memory.
     *
     * @return The length of the deflated buffer.
     * @since v0.8.1
     */
    static ssize_t inflateMemory(unsigned char* in, ssize_t inLength, unsigned char** out);

    /**
     * Inflates either zlib or gzip deflated memory. The inflated memory is expected to be freed by the caller.
     *
     * @param outLengthHint It is assumed to be the needed room to allocate the inflated buffer.
     *
     * @return The length of the deflated buffer.
     * @since v1.0.0
     */
    static ssize_t inflateMemoryWithHint(unsigned char* in,
                                         ssize_t inLength,
                                         unsigned char** out,
                                         ssize_t outLengthHint);

    /**
     * Inflates a GZip file into memory.
     *
     * @return The length of the deflated buffer.
     * @since v0.99.5
     */
    static int inflateGZipFile(const char* filename, unsigned char** out);

    /**
     * Test a file is a GZip format file or not.
     *
     * @return True is a GZip format file. false is not.
     * @since v3.0
     */
    static bool isGZipFile(const char* filename);

    /**
     * Test the buffer is GZip format or not.
     *
     * @return True is GZip format. false is not.
     * @since v3.0
     */
    static bool isGZipBuffer(const unsigned char* buffer, ssize_t len);

    /**
     * Inflates a CCZ file into memory.
     *
     * @return The length of the deflated buffer.
     * @since v0.99.5
     */
    static int inflateCCZFile(const char* filename, unsigned char** out);

    /**
     * Inflates a buffer with CCZ format into memory.
     *
     * @return The length of the deflated buffer.
     * @since v3.0
     */
    static int inflateCCZBuffer(const unsigned char* buffer, ssize_t len, unsigned char** out);

    /**
     * Test a file is a CCZ format file or not.
     *
     * @return True is a CCZ format file. false is not.
     * @since v3.0
     */
    static bool isCCZFile(const char* filename);

    /**
     * Test the buffer is CCZ format or not.
     *
     * @return True is CCZ format. false is not.
     * @since v3.0
     */
    static bool isCCZBuffer(const unsigned char* buffer, ssize_t len);

    /**
     * Sets the pvr.ccz encryption key parts separately for added security.
     *
     * Example: If the key used to encrypt the pvr.ccz file is
     * 0xaaaaaaaabbbbbbbbccccccccdddddddd you will call this function 4
     * different times, preferably from 4 different source files, as follows
     *
     * ZipUtils::setPvrEncryptionKeyPart(0, 0xaaaaaaaa);
     * ZipUtils::setPvrEncryptionKeyPart(1, 0xbbbbbbbb);
     * ZipUtils::setPvrEncryptionKeyPart(2, 0xcccccccc);
     * ZipUtils::setPvrEncryptionKeyPart(3, 0xdddddddd);
     *
     * Splitting the key into 4 parts and calling the function from 4 different source
     * files increases the difficulty to reverse engineer the encryption key.
     * Be aware that encryption is *never* 100% secure and the key code
     * can be cracked by knowledgable persons.
     *
     * IMPORTANT: Be sure to call setPvrEncryptionKey or
     * setPvrEncryptionKeyPart with all of the key parts *before* loading
     * the sprite sheet or decryption will fail and the sprite sheet
     * will fail to load.
     *
     * @param index Part of the key [0..3].
     * @param value Value of the key part.
     */
    static void setPvrEncryptionKeyPart(int index, unsigned int value);

    /**
     * Sets the pvr.ccz encryption key.
     *
     * Example: If the key used to encrypt the pvr.ccz file is
     * 0xaaaaaaaabbbbbbbbccccccccdddddddd you will call this function with
     * the key split into 4 parts as follows
     *
     * ZipUtils::setPvrEncryptionKey(0xaaaaaaaa, 0xbbbbbbbb, 0xcccccccc, 0xdddddddd);
     *
     * Note that using this function makes it easier to reverse engineer and discover
     * the complete key because the key parts are present in one function call.
     *
     * IMPORTANT: Be sure to call setPvrEncryptionKey or setPvrEncryptionKeyPart
     * with all of the key parts *before* loading the spritesheet or decryption
     * will fail and the sprite sheet will fail to load.
     *
     * @param keyPart1 The key value part 1.
     * @param keyPart2 The key value part 2.
     * @param keyPart3 The key value part 3.
     * @param keyPart4 The key value part 4.
     */
    static void setPvrEncryptionKey(unsigned int keyPart1,
                                    unsigned int keyPart2,
                                    unsigned int keyPart3,
                                    unsigned int keyPart4);

private:
    static int inflateMemoryWithHint(unsigned char* in,
                                     ssize_t inLength,
                                     unsigned char** out,
                                     ssize_t* outLength,
                                     ssize_t outLengthHint);
    static inline void decodeEncodedPvr(unsigned int* data, ssize_t len);
    static inline unsigned int checksumPvr(const unsigned int* data, ssize_t len);

    static unsigned int s_uEncryptedPvrKeyParts[4];
    static unsigned int s_uEncryptionKey[1024];
    static bool s_bEncryptionKeyIsValid;
};

// forward declaration
struct ZipEntryInfo;
struct ZipFilePrivate;

/**
 * Zip file - reader helper class.
 *
 * It will cache the file list of a particular zip file with positions inside an archive,
 * so it would be much faster to read some particular files or to check their existence.
 *
 * @since v2.0.5
 */
class AX_DLL ZipFile
{
public:
    static ZipFile* createFromFile(std::string_view zipFile, std::string_view filter = ""sv);

    virtual ~ZipFile();

    bool initWithFile(std::string_view zipFile, std::string_view filter = ""sv);

    /**
     * Regenerate accessible file list based on a new filter string.
     *
     * @param filter New filter string (first part of files names)
     * @return true whenever zip file is open successfully and it is possible to locate
     *              at least the first file, false otherwise
     *
     * @since v2.0.5
     */
    bool setFilter(std::string_view filter);

    /**
     * Check does a file exists or not in zip file
     *
     * @param fileName File to be checked on existence
     * @return true whenever file exists, false otherwise
     *
     * @since v2.0.5
     */
    bool fileExists(std::string_view fileName) const;

    /**
     * Get files and folders in pathname
     *
     * @param dirname
     * @return
     */
    std::vector<std::string> listFiles(std::string_view pathname) const;

    /**
     * Get resource file data from a zip file.
     * @param fileName File name
     * @param[out] buffer If the file read operation succeeds, if will contain the file data.
     * @return True if successful.
     */
    bool getFileData(std::string_view fileName, ResizableBuffer* buffer);

    std::string getFirstFilename();
    std::string getNextFilename();

    /**
     * zipFile Streaming support, !!!important, the file in zip must no compress level, otherwise
     *  stream seek doesn't work.
     */
    ZipEntryInfo* vopen(std::string_view fileName);
    int vread(ZipEntryInfo*, void* buf, unsigned int size);
    int64_t vseek(ZipEntryInfo*, int64_t offset, int origin);
    void vclose(ZipEntryInfo*);
    int64_t vsize(ZipEntryInfo*);

private:
    ZipFile();

    int getCurrentFileInfo(std::string* filename, unz_file_info_s* info);

    /** Internal data like zip file pointer / file list array and so on */
    ZipFilePrivate* _data;
};

} // end of namespace ax

// end group
/// @}

/// @endcond
#endif  // __SUPPORT_ZIPUTILS_H__
